Optical Fiber Fabry–Pérot Pressure Sensor Based on a Polymer Structure

A novel optical MEMS pressure sensor with a SU-8 microstructure is proposed. SU-8 photoresist is used to form the high aspect ratio structure on silicon wafer. The advantage of the novel structure mainly lies in the design of separating sensing membrane deformation with the length change of Fabry-Pérot cavity. The principle of the pressure measurement has been introduced. The mechanical model is analyzed and parameters of SU-8 structure are determined by simulation. The fabrication process is described. Experimental results demonstrate that the sensor has a reasonable linearity, sensitivity under micro-pressure measurement range from 0 to 0.1 MPa.